Method of wrapping round bales

ABSTRACT

A method of wrapping cylindrical bales of crop material with sheet material, such as net or plastic film, includes gripping a tail of the sheet material in a dispensing mechanism during formation of a cylindrical bale in a bale forming chamber of an agricultural baler. After the bale is completed, the dispensing mechanism is moved from a retracted position to a dispensing position and the tail of the sheet material is inserted into the bale forming chamber of the baler. The sheet material is wrapped circumferentially around the bale while it is disposed in the bale forming chamber, and the dispensing mechanism is returned to the retracted position after one or more layers of the sheet material have been wrapped around the bale. When the dispensing mechanism has returned to the retracted position, the sheet material is cut by a cutting mechanism.

BACKGROUND OF THE INVENTION

This invention relates generally to agricultural balers typicallyreferred to as round balers which form cylindrical (i.e. round) bales ofcrop material and, in particular, to a method of wrapping such bales.

Prior methods of wrapping cylindrical bales of crop material with sheetmaterial such as net or plastic film have typically required the use offeed rollers to dispense the sheet material into a round baler. Examplesof these prior methods are disclosed in U.S. Pat. Nos. 4,366,665 to R.M. Van Ginhoven et al; 4,599,844 to G. Clostermeyer et al; 4,604,855 toKrone et al; 4,697,402 to H. D. Anstey et al; 4,729,213 to J. L. M.Raes; and 4,790,125 to J. H. Merritt. One of the drawbacks of the priormethods is that the sheet material tends to wrap around and get tangledup on the feed rollers. Another drawback of the prior methods is thehigh cost of using the feed rollers to dispense the sheet material.

SUMMARY OF THE INVENTION

The present invention provides a method of wrapping cylindrical bales ofcrop material with sheet material such as net or plastic film withoututilizing feed rollers.

The method of the present invention comprises the steps of gripping atail of the sheet material in dispensing means during formation of acylindrical bale of crop material in a bale forming chamber of anagricultural baler, moving the dispensing means from a retractedposition to a dispensing position after completion of the cylindricalbale, inserting the tail of the sheet material into the bale formingchamber when the dispensing means is in the dispensing position,wrapping the sheet material circumferentially around the cylindricalbale while it is disposed in the bale forming chamber, and moving thedispensing means from the dispensing position to the retracted positionafter at least one layer of the sheet material has been wrappedcircumferentially around the cylindrical bale. The method may alsocomprise the step of cutting the sheet material when the dispensingmeans is in the retracted position.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a round baler incorporating amethod of wrapping bales according to the preferred embodiment of thepresent invention;

FIG. 2 is an enlarged side elevational view of a portion of the roundbaler of FIG. 1 illustrating the bale wrapping method of the presentinvention;

FIG. 3 is an enlarged view of part of the round baler of FIG. 1;

FIG. 4 is a view taken in the direction of arrows 4--4 in FIG. 3;

FIG. 5 is a view taken in the direction of arrows 5--5 in FIG. 3; and

FIG. 6 is a view taken in the direction of arrows 6--6 in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a round baler 10 incorporating a method accordingto the present invention includes a main frame 12 supported by a pair ofwheels 14. A tongue 16 is provided on the forward portion of the mainframe 12 for connection to a tractor (not shown). A tailgate 18 ispivotally connected to the main frame 12 by stub shafts 20 so that thetailgate 18 may be closed as shown in FIG. 1 during bale formation oropened to discharge a completed bale. A conventional pickup 22 ismounted on the main frame 12 and is supported by a pair of wheels (notshown). The pickup 22 includes a plurality of fingers or tines 24movable in a predetermined path to lift crop material from the groundand deliver it rearwardly toward a floor roll 26 which is rotatablymounted on the main frame 12.

A sledge assembly 28 includes a plurality of rollers 30, 32, 34extending transversely of the main frame 12 in an arcuate arrangementbest seen in FIG. 2. The rollers 30, 32, 34 are journalled at the endsthereof in a pair of spaced apart arms 36. These arms 36 are pivotallymounted inside the main frame 12 on stub shafts 38 for permittingmovement of the sledge assembly 28 between a bale starting positionshown in broken lines in FIG. 1 and a full bale position shown in solidlines in FIG. 1. The rollers 30, 32, 34 are driven in a counterclockwisedirection as viewed in FIGS. 1 and 2 by conventional means (for example,chains and sprockets or gears) connected with a drive shaft 17 which isadapted for connection to the power take off of a tractor (not shown). Astripper roll 39 is located adjacent roller 30 and is driven in acounterclockwise direction, as viewed in FIG. 2, to strip crop materialfrom the roller 30. An idler roller 40 is carried by the arms 36 formovement in an arcuate path when the sledge assembly 29 moves betweenits bale starting and full bale positions. The idler roller 40 is freelyrotatable.

An apron 42 includes a plurality of flat belts arranged side-by-side andsupported on guide rolls 44, 46, 48, 50, 52 which are rotatably mountedin the tailgate 18. The apron 42 is also supported on a drive roll 54which is rotatably mounted in the main frame 12. Although the apron 42passes between the roller 34 and the idler roller 40, it is inengagement with only the idler roller 40 but the roller 34 is located inclose proximity to the apron belts to strip crop material from the apron42. Further conventional means (not shown) are connected with the driveshaft 17 to provide rotation of the drive roll 54 in a direction whichcauses movement of the apron 42 along the path indicated in broken linesin FIG. 1. An additional guide roll 55 in the main frame 12 ensuresproper driving engagement between the apron 42 and the drive roll 54. Apair of take up arms 56 are pivotally mounted on the main frame 12 by across shaft 58 for movement between inner and outer positions shown inFIG. 1. Take up arms 56 carry additional guide rolls 60 and 62 forsupporting the apron 42. Resilient means (not shown) are provided tonormally urge the take up arms 56 toward their inner positions whileresisting movement thereof from their inner positions to their outerpositions.

When the round baler 10 is in the condition shown in FIG. 1 with thetailgate 18 closed, an inner course 42a of the apron 42 extendingbetween the guide roll 44 and the idler roller 40 cooperates with therollers 30, 32, 34 of the sledge assembly 28 to define a bale formingchamber. The apron inner course 42a forms a rear wall of the chamberwhile the rollers 30, 32, 34 form a front wall of the chamber. The floorroll 26 is disposed in the bottom of the chamber between the front andrear walls thereof, and the roller 30 is spaced from the floor roll 26to form a throat or inlet for the chamber.

As the round baler 10 is towed across a field by a tractor (not shown),the pickup tines 24 lift crop material from the ground and deliver itthrough the throat formed between the floor roll 26 and the roller 30into the bale forming chamber of the baler 10. The crop material iscarried rearwardly by the floor roll 26 into engagement with the aproninner course 42a which carries it upwardly and forwardly into engagementwith the rollers 30, 32, 34. The crop material is coiled in a clockwisedirection as viewed in FIG. 1 to start a bale core. Continued feeding ofcrop material into the bale forming chamber by the pickup tines 24causes the apron inner course 42a to expand in length around a portionof the circumference of the bale core as the diameter thereof increases.The take up arms 56 rotate from their inner position shown in FIG. 1toward their outer position to permit such expansion of the apron innercourse 42a. When a bale has been formed and then wrapped as describedlater with sheet material such as net or plastic film, the tailgate 18is opened by conventional means (for example, hydraulic cylinders) andthe bale is ejected. Subsequent closing of the tailgate 18 returns theapron inner course 42a to the location shown in FIG. 1, and the roundbaler 10 is ready to form another bale.

It will be understood that during formation of a bale, sledge assembly28 moves from its bale starting position to its full bale position. Thismovement of the sledge assembly 28 causes the idler roller 40 to move inan arcuate path while maintaining the apron 42 in close proximity to theroller 34, thereby allowing the roller 34 to strip crop material fromthe apron 42 but preventing the loss of crop material between the roller34 and the apron 42 during formation of a bale. The sledge assembly 28is pushed outwardly toward its full bale position during bale formationand is pulled inwardly toward its bale starting position during baleejection without utilizing any additional mechanisms.

In an alternative embodiment of the round baler 10 which is not shown,apron 42 consists of a pair of chains connected together at spacedintervals by transverse slats, and the idler roller 40 is replaced by apair of idler sprockets engaged with the chains. Also in thisalternative embodiment, the guide rolls 44, 46, 48, 50, 52, 55, 60, 62would be replaced with guide sprockets for engaging the apron chains,and the drive roll 54 would be replaced by drive sprockets.

Bale wrapping apparatus 64 shown in FIG. 1 includes a dispensingmechanism 66 pivotally mounted on the sledge assembly 28 and a cuttingmechanism 68 pivotally mounted on the main frame 12. As best seen inFIGS. 3 and 4, the dispensing mechanism 66 comprises a pair of levers 70spaced apart but connected by a frame member 71. The levers 70 arerotatably supported on a cross tube 72 that extends between the arms 36of the sledge assembly 28. Each lever 70 is attached to the cross tube72 by a clevis 74, and bolts 76 fasten each clevis 74 to brackets 78fixed to the levers 70. A stop 73 is carried on one of the levers 70 forengagement with one of the arms 36 of the sledge assembly 28 to limitpivoting movement of the dispensing mechanism 66 in a counterclockwisedirection as viewed in FIG. 2.

The dispensing mechanism 66 also comprises clamping members 80, 82extending transversely of the baler 10 between the levers 70 andarranged to dispense sheet material S such as net or plastic film from asupply roll R disposed in a container 83 carried on the baler main frame12 Container 83 has a lid 85 which may be opened to permit removal ofthe supply roll R. Clamping members 80 and 82 are mounted respectivelyon bars 84 and 86 which extend between the levers 70. Springs 88 andlinks 90 are arranged to urge the clamping member 82 against theclamping member 80. Each spring 88 is connected at one end to one of thelinks 90 and at the other end to an eye bolt 92 that is fastened to aflange member 94 on one of the brackets 78. The links 90 are engagedwith the clamping member 82 in a manner which, due to springs 88, urgesthe clamping member 82 in a clockwise direction in FIG. 3 about the rod86. As the sheet material S is dispensed from the supply roll R by thedispensing mechanism 66, it passes over a roller shaft 95 which ismounted in and extends transversely of the baler main frame 12.

Referring to FIG. 2, bale wrapping apparatus 64 also includes a powersource such as an electric motor 96 mounted on the main frame 12 with anoutput shaft 97 thereof connected to a large sprocket 98 by a drivechain 100. Another drive chain 102 connects a small sprocket 104 (whichis attached to large sprocket 98) with a sprocket 106. A further drivechain 108 connects a small sprocket 110 (which is attached to sprocket106) and a small sprocket 112. A first link 114 is pinned at one end todrive chain 108 and pivoted at the other end to a second link 116. Athird link 118 is pivotally connected between the second link 116 andone of the levers 70 of the dispensing mechanism 66.

The cutting mechanism 68 includes a pair of spaced apart arms 120rotatably supported on a shaft 122. A knife 124 is carried by andextends transversely between the arms 120 for engagement with the sheetmaterial S dispensed by the dispensing mechanism 66. The arms 120 arerotated on the shaft 122 by means (not shown) such as a cam actuatedlinkage connected between one of the arms 120 and the link 114. Theclamping members 80 and 82 of the dispensing mechanism 66 include upperand lower plates 126 and 128, respectively, between which the sheetmaterial S is fed. Upper plate 126 has a leading edge 126a with aplurality of generally semicircular notches 127 formed therein as shownin FIG. 5 while lower plate 128 has a leading edge 128a with a pluralityof serrated teeth 129 formed therein as shown in FIG. 6.

When a bale B has been formed in the round baler 10 and it is desired towrap the bale B with the sheet material S, the electric motor 96 isactivated while the apron 42 continues to rotate the bale B in aclockwise direction as viewed in FIG. 2. The output shaft 97 of theelectric motor 96 drives the sprocket 106 via chains 100, 102. Sprocket110 drives sprocket 112 via chain 108 which causes movement of the links114, 116, 118 from the solid line positions of FIG. 2 to the broken linepositions of FIG. 2. This rotates the dispensing mechanism 66 from aretracted position shown in solid lines in FIG. 2 to a dispensingposition shown in broken lines in FIG. 2. In the retracted position ofthe dispensing mechanism 66, a tail T of the sheet material S is grippedby the clamping members 80, 82 thereby preventing the sheet material Sfrom being fed into the bale forming chamber of the baler 10. However,in the dispensing position of the dispensing mechanism 66, the tail T ofthe sheet material S is inserted into the bale forming chamber and sheetmaterial S is dispensed from the supply roll R into the bale formingchamber.

As the dispensing mechanism 66 moves toward its dispensing position, thecutting mechanism 68 is rotated clockwise to the position shown in FIG.2 and the clamping members 80, 82 move into a gap 35 between the roller34 and the apron 42. The tail T of the sheet material S gripped betweenthe clamping members 80, 82 is inserted through the gap 35 into the baleforming chamber where it is caught between the roller 34 and the bale Bwhich are rotating in opposite directions. The sheet material S is thendispensed from the supply roll R, over the roller shaft 95, between theclamping members 80 and 82, and then through the gap 35 into the baleforming chamber where it is wrapped circumferentially around the bale Bwhile the bale B continues to be rotated by the apron 42.

After the bale B has been wrapped with one or more layers of the sheetmaterial S, the electric motor 96 is reversed thereby moving thedispensing mechanism 66 from the dispensing position shown in brokenlines in FIG. 2 to the retracted position shown in solid lines in FIG.2. The links 114, 116, 118 move back to their solid line positions ofFIG. 2. When the dispensing mechanism 66 has returned to its retractedposition, the cutting mechanism 68 is rotated counterclockwise as viewedin FIG. 2 so that the knife 124 is brought downwardly into contact withthe sheet material S extending from the clamping members 80, 82 of thedispensing mechanism 66. The knife 124 cuts the sheet material S butleaves another tail T which is gripped by the clamping members 80, 82for future insertion into the bale forming chamber whenever the nextbale is ready to be wrapped with the sheet material S.

The details of the upper and lower plates 126 and 128, respectively, areshown in FIGS. 5 and 6. Notches 127 formed in the leading edge 126a ofupper plate 126 prevent the tail T of the sheet material S from beingcarried out of the gap 35 by the apron 42 when the dispensing mechanism66 is in the dispensing position. When the dispensing mechanism 66 is inthe dispensing position, apron 42 has a tendency to grab the sheetmaterial S and feed it back out of the bale forming chamber of the baler10 as the apron 42 tracks around the guide roller 40. This tendency ofthe apron 42 is overcome by providing the leading edge 126a of the upperplate 126 with notches 127 which prevent backfeeding of the sheetmaterial S. In other words, the notches 127 insure proper dispensing ofthe sheet material S from the supply roll R into the bale formingchamber of the baler 10. The serrated teeth 129 are provided in theleading edge 128a of lower plate 128 for the purpose of allowing thesheet material S to spread to its nominal width as it is being dispensedfrom the supply roll R. As seen in FIG. 6, the serrated teeth 129 areslanted outwardly in opposite directions (i.e. left and right) beginningnear the center of the lower plate 128. This orientation of the teeth129 allows the sheet material S to spread transversely acrosssubstantially the full width of the bale forming chamber of the baler 10and keeps the sheet material S spread while it is being wrappedcircumferentially around a cylindrical bale disposed in the bale formingchamber. Teeth 129 also prevent the sheet material S from retractingafter it has been cut by the knife 124 thereby assuring the formation ofthe tail T.

What is claimed is:
 1. In combination with an agricultural baler of thetype having a bale forming chamber in which cylindrical bales of cropmaterial are formed, a method of wrapping the cylindrical bales withsheet material, said method comprising the steps of:gripping a tail ofthe sheet material in dispensing means between a pair of clampingmembers during formation of a cylindrical bale of crop material in thebale forming chamber of the agricultural baler; pivoting said dispensingmeans about a generally horizontal axis from a retracted position to adispensing position after completion of the cylindrical bale; insertingsaid tail of the sheet material into said bale forming chamber when saiddispensing means is in said dispensing position; wrapping the sheetmaterial circumferentially around the cylindrical bale while it isdisposed in said bale forming chamber; and pivoting said dispensingmeans about said horizontal axis from said dispensing position to saidretracted position after at least one layer of the sheet material hasbeen wrapped circumferentially around the cylindrical bale.
 2. Themethod of claim 1, further comprising the step of cutting the sheetmaterial when said dispensing means is in said retracted position. 3.The method of claim 1, wherein said gripping step includes preventingthe sheet material from being dispensed when said dispensing means is insaid retracted position.
 4. The method of claim 1, wherein saidinserting step is performed without utilizing feed rollers.
 5. Themethod of claim 2, wherein said cutting step includes rotating a knifeinto engagement with the sheet material.
 6. The method of claim 1,wherein said moving steps are performed by using power means connectedto said dispensing means.
 7. The method of claim 1, wherein saidwrapping step includes rotating the cylindrical bale in said baleforming chamber as the sheet material is wrapped circumferentiallyaround the cylindrical bale.